1. Field of the Invention
The present invention relates to an ink jet printer of a hot melt type for heat-melting a solid ink stored in an ink tank and ejecting the resulting liquid ink to effect printing.
2. Description of Related Art
Known heretofore is a hot melt type ink jet printer that heats and melts a solid ink and performs printing by using the resulting liquid ink. In the use of such a solid ink, ink sediment and dust are apt to be deposited on a nozzle surface of an ink jet head, and air is apt to stay in passages within the ink jet head. Consequently, the orifice of the nozzle is apt to be clogged. This clogging of the orifice has heretofore been a cause of bad influence on the print quality.
In an effort to eliminate such inconvenience there have been proposed cleaning methods involving cleaning of the ink jet head periodically or as necessary to maintain the required performance of the ink jet. For example, one method uses replaceable cleaning paper that is disposed face to face with the nozzle of the ink jet head and is brought into contact with the ink jet head under the application of a predetermined certain force to wipe off the deposited ink. Another method uses a cleaning device in which ink is ejected forcibly from the nozzle, thereby allowing dust and air included in the nozzle to be adhered to the aforesaid cleaning paper spaced slightly from the nozzle. This method is disclosed in, for example, Japanese Unexamined Patent Publication Nos. Sho 62-25056 (1987) and Hei 5-42677 (1993).
However, in the case where wiping is performed while allowing a wiping member such as cleaning paper to be in contact with the ink jet head, the heat of the nozzle portion and the vicinity thereof is removed by the cleaning paper or the like, resulting in the nozzle temperature dropping. Thus, printing cannot be done until elevation of the nozzle temperature. In the foregoing Japanese Unexamined Patent Publication No. Hei 5-42677 it is described to heat the cleaning paper. But even with mere heating of the cleaning paper, unless the heating temperature is above the nozzle temperature, there will arise a drop in temperature of the nozzle portion due to the wiping operation.